Sodium hydroxide (NaOH)
Commonly known as caustic soda, white crystal at room temperature with strong corrosiveness. Easily soluble in water and its solution is strongly alkaline to make phenolphthalein red. Sodium hydroxide is a very common alkali and is one of the chemical lab essential drugs. It is easy to absorb water vapor in the air, so it must be kept under seal and use rubber stopper. Its solution can be used as washing liquid.
Density: 2.130g/m3
Melting point: 318.4℃
Water solubility: Easily soluble in water, aqueous solution is colorless
Boiling point: 1390℃
Alkali dissociation constant (Kb) = 3.0
Alkali dissociation constant reciprocal logarithm (pKb) = -0.48
Lethal dose: 40mg/kg